


Assumptions

by A Sirius Crush On Moony (Obsession137)



Category: Harry Potter - J. K. Rowling
Genre: Incest, M/M, Rated M, Slash
Language: English
Status: Completed
Published: 2015-05-30
Updated: 2015-05-30
Packaged: 2018-04-02 01:48:11
Rating: Mature
Warnings: Underage
Chapters: 1
Words: 1,980
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4041004
Author URL: https://archiveofourown.org/users/Obsession137/pseuds/A%20Sirius%20Crush%20On%20Moony
Summary: <blockquote class="userstuff">
              <p>Regulus is deeply in love with Sirius, unbeknownst to Sirius. How can he not stare when he accidentally walks in on Sirius pleasuring himself?</p>
            </blockquote>





	Assumptions

Regulus Black knew that there was something terribly wrong with him somewhere inside. How could there not be? He spent every waking moment thinking of Sirius, and every night dreaming of Sirius – and not in a nice, friendly, brotherly way. No, quite the opposite actually.

It had taken him a fair few months to realise that these weird thoughts and disturbing feelings meant one thing – he had fallen in love with Sirius.

When the realisation hit him, he refused to look at himself in the mirror. He didn't want to see the guilt in his own eyes reflected back at him. He refused to acknowledge Sirius at school or at home, hoping that it would make the feelings just disappear. He even went as far as to get himself a girlfriend, which lasted all of two days because he just knew in his heart of hearts that he was gay.

It was the summer holidays, and Regulus was lying on his bed staring up at the ceiling. He tried to think of anything that would pop into his head to refrain from thinking about Sirius.

_The colour of my ceiling kind of looks like the same colour as the fireplace in the Common Room at Hogwarts. Yeah. Maybe slightly lighter, but the same colour more or less. I miss the Common Room. I miss Hogwarts. I miss walking down the corridors and walking past Sirius and feeling my heart beat faster. NO NO NO STOP. Ugh. The ceiling is so high in our house. It's weird. I wonder if other houses have high ceilings. Sirius is next door, I just want to go in there and- NO._

He soon decided it was no use trying to stop himself from thinking about Sirius. It was inevitably going to happen.

Regulus was getting hungry, made his way downstairs. As he passed Sirius's room, the door was left open a crack, and Regulus just happened to catch a glance at something that made him stop, rooted to the spot.

He wanted to look so badly, but he knew it was wrong and a very bad idea.

 _But Sirius is in there_ , he whined to himself, and he found that his eyes moved like magnets to peek in at Sirius, who was lying on his bed completely naked. Regulus watched in silence as Sirius's hand grasped at his hard cock, stroking it up and down slowly. Sirius's eyes were shut and he was making small sounds that turned Regulus on like crazy.

He knew he needed to go, but he physically couldn't. His eyes were glued to Sirius.

 _He's so hot_.

Regulus could feel his cock getting harder beneath his robes and he instinctively reached down to play with himself as he watched Sirius.

It felt like one of his most erotic dreams had come to life, and if Sirius just happened to open his eyes right now...

Regulus didn't care in that moment. It felt  _so_  good, touching himself to the sight of Sirius masturbating right in front of him.

To his utter horror, he emitted a low moan, and he watched as Sirius opened his eyes and glance up at him. Everything happened so quickly; Sirius scrambled to grab the duvet to cover himself up, his cheeks turned a dark crimson colour, Regulus slammed the door shut and ran into his room, feeling completely ashamed and embarrassed.

How could he have been so stupid? Surely he should have known that Sirius would open his eyes eventually.

 _But damn, that was hot_.

He lay in his bed in silence for Merlin knows how long. All he could hear was his heart beating loudly in his chest like a drum. Just as he was falling asleep, he heard a half-hearted knock on his door. He gulped and sat up.

He wanted to say "come in," but it ended up more like a strangled, "c-c-come in."

He heard the door opening but refused to look up. He could feel his cheeks burning. He heard the door close again and felt a weight coming down on the mattress.

_Oh Merlin, he's sitting on my bed. Keep cool, keep cool._

Sirius cleared his throat. "Er-" he started. "-this is awkward."

Regulus finally looked up into Sirius's dark grey eyes. He tried not to get lost in them as he spoke. "Sorry," he mumbled.

"Sorry for what?" Sirius asked, going a little red. "I shouldn't have left my damned door open."

"F-f-for watching," Regulus whispered.

Sirius looked confused and then alarmed. "You were watching?"

"I-I-I d-d-didn't mean-"

"- I thought you were just walking past and that's when I opened my eyes."

 _Crap,_  Regulus thought.  _I shouldn't have mentioned it._

"Sorry," he said again, feeling mortified.

There was a moment of complete silence, and Regulus was sure he'd never felt so awkward in his entire life.

"Why were you watching?" Sirius asked.

"I don't know."

"You must know why," Sirius said.

" _I don't know, Sirius_!" Regulus hissed, feeling annoyed. Couldn't his secrets stay secret?

"Maybe you need a girlfriend or something, I don't know," Sirius said, with a forced calmness in his voice.

"No."

"No?"

"I'm gay," Regulus said, before he could stop himself. He looked down at his hands. Looking at Sirius was too painfully embarrassing.

"Oh," Sirius replied. "Oh."

"Okay," Regulus said.

"I'm gay too," Sirius whispered.

Regulus sighed and looked at Sirius with a small smile. "Okay," he said. What else was he supposed to say to that? –  _Oh, cool! Let's be gay together!_

"Do you have a boyfriend?" Sirius asked, in an obvious attempt to divert the conversation away from what had happened earlier.

"No."

"Got your eye on anyone?"

"Yes," Regulus mumbled, going red again.

"Who?" Sirius asked.

"Nobody."

"Come on," Sirius said playfully. "You can tell me."

"So you can spread it round the whole school? No thanks," Regulus replied. He knew he wouldn't spread it round the school, but it was a better excuse than, " _No I can't tell you because it's you I love."_

"Would I do that?" Sirius asked.

"No. I just can't tell you."

"Why not?"

One thing Regulus couldn't stand about Sirius was how persistent he was with everything. He would pester you and pester you until you told him something.

"Take a wild guess, Sirius."

Sirius sat for a moment, pondering. Regulus doubted he would get it. He wouldn't have said it otherwise.

Sirius glanced sideways at him, looking a mix of emotions that Regulus couldn't quite decipher.

"You  _do_  know I'm your brother, right?" he asked.

Regulus's heart was pounding.

"Yes," he croaked.

"Now correct me if I'm wrong," Sirius said slowly. "You have feelings for-"

"-Stop," Regulus said quickly. "Yes, I have feelings for you and I know it's wrong and disgusting, but I just couldn't listen to you say it out loud because you'll probably hate me and think I'm a creep."

"Huh?" Sirius asked, looking shocked.

"You heard me."

"Wait, wait, wait," Sirius said quickly. "I thought you had feelings for one of my best mates."

Regulus let out a nervous laugh and internally kicked himself for making another stupid assumption about what Sirius was going to say.

Sirius pursed his lips and smiled awkwardly.

"Yeah," Regulus said, trying desperately to make conversation. "Anyway."

"Reg, that's weird."

Regulus felt as though he might throw up. "Yeah, I know," he mumbled quietly.

"No, it's  _really_  weird," Sirius said. "I don't even know what to say to that."

"Just forget it, please."

"How can I forget that my little brother has sexual feelings for me?" Sirius replied, looking uncomfortable.

"I d-didn't say they were s-sexual," Regulus said quietly.

Sirius raised his eyebrows. "Of course they are. You were standing there watching me – oh Merlin."

"I'm sorry."

Sirius let out a deep sigh and cleared his throat. "Okay, awkwardness aside."

"Yes?"

"Have you tried, you know, getting rid of these, er, feelings?"

"I've tried."

"Oh. How?"

"I um, t-tried to um, I just can't t-talk about it."

Sirius smiled slightly. "It's okay, Reg," he said. "I don't hate you or anything."

Regulus looked up, feeling relief wash over him. "You don't?"

"Of course not. It's weird, but I guess I'm kinda flattered."

"Thanks," Regulus said, blushing again. "Can we talk about something else please?"

"Sure. So, you're gay," Sirius said. "Have you kissed a guy?"

"No, have you?" Regulus asked.

"Yeah," Sirius replied. "I've been told that I'm a pretty good kisser."

"Oh, that's... nice."

 _Is he trying to torture me or something_ , Regulus thought.

They sat for a minute in silence, with Sirius looking at Regulus in a weird way. Regulus finally rolled his eyes.

"What?" he said.

"Nothing. I was just thinking."

"Thinking about what?"

"What we were talking about before," Sirius said.

"Please don't," Regulus pleaded, feeling awkward once more.

"It kinda makes me want to kiss you," Sirius whispered, staring into Regulus's eyes.

"W-what?" Regulus blinked.

"I've kissed plenty of guys, but you're more interesting."

"Because I'm your brother," Regulus said.

"I want to kiss you."

"Oh Merlin," Regulus breathed, trying not to smile like a maniac.

"Do you want me to kiss you?" Sirius asked.

"More than anything."

"Tell me what you want."

"I w-want you to kiss me," Regulus said. He couldn't believe this was happening. He couldn't believe these words were coming out of his mouth.

"That's not good enough."

Regulus couldn't help thinking that Sirius was being flirty with him.

"Kiss me," Regulus said.

Before Regulus knew what was happening, Sirius was kissing him and every thought in his head became tangled up in a swirling storm of emotions. The feeling of Sirius's lips on his was like none other. The tingling over his entire body and the light-headedness and the electricity running between them.

Sirius's hand was suddenly tangled in Regulus's hair and Regulus was being pushed back onto the bed. All the time, their lips were connected.

Sirius was straddling him, and Regulus felt a tongue slip into his mouth. The kiss grew more and more heated and he felt a pleasant tingling sensation run up his spine when he felt Sirius's erection brush against his own. He heard Sirius moan into his mouth and Regulus could barely believe that this was real.

It took all of Regulus's strength and self-control to finally push Sirius off of him. Both boys were panting loudly, as they sat up and glanced at each other with flushed faces.

"Man," Sirius said, running a hand through his hair. "Man, that was just,  _damn_."

Regulus smiled. "Yeah, it was."

"Why'd you stop?"

"Because."

Sirius raised his eyebrows. "I was just about to go down on you."

"Ooookay!" Regulus said, flushing. "I just couldn't. I l-love you too much to do that."

"You love me?"

"I am in love with you," Regulus said. "And I may be a fool because I know that nothing else will ever happen between us, but I just didn't want to do  _that_  with you just yet. I wanted to go slow."

Sirius smiled and took his hand. "I understand."

"Thank you."

"I can't promise that anything else will happen between us, but I'll think about it. It's a lot to get my head around."

"You'll think about it?" Regulus asked, feeling his heart rate pick up.

"Yes."

"Thank you, Sirius," Regulus exclaimed, flinging himself towards Sirius and wrapping his arms around him. He didn't care how ridiculous he was being, because Sirius 'thinking about it' gave him that small sliver of hope that could lead to so many amazing things.

Sirius held onto him and laughed a little. "I love you."

Regulus knew Sirius didn't mean it in the same way he meant it, but it made him smile nevertheless. The fact that Sirius could possibly mean it one day was the only thing Regulus needed.

With a satisfied smile, Regulus said, "I love you, too."


End file.
